Wheel Kit, includes 1 pair of 6" black blow-molded (hollow) plastic wheels and steel axle caps, designed to fit 3/8" axle shaft. Axle caps are press-fit, no special tools required. For battery chargers with 3/8" axle shaft. Also used on barbecue grills and other light equipment, check dimensions for proper fit. Specifications: Load Rating: 25 lbs. (each wheel) Material: Plastic (hollow, blow-molded) Color: Black Outside Diameter: 6.10" (155mm) Track Width: 1.57" (40mm) Hub Offset (spaces wheel tread from cabinet): 0.16" (4mm) Hub Width at Axle Tube (length of bore): 1.35" (34mm) Axle Bore Diameter: 0.40" (10.2mm) (accommodates 3/8" or 10mm diameter axle) Warranty: 90 Day Limited Warranty against manufacturing defects.